On May 19, wedding bells will ring outside London as American actress Meghan Markle exchanges vows with Prince Harry, making history as the first biracial divorcée to marry into the royal family. British journalist Andrew Morton, who will be at the wedding as a commentator, has written a new biography of Markle called Meghan: A Hollywood Princess (Grand Central). Morton first made an international splash in 1992 with his best-selling tell-all Diana: Her True Story, which exposed the unhappy marriage of Harry’s parents, Princess Diana and Prince Charles. Morton spoke with USA TODAY’s Jocelyn McClurg during a #BookmarkThis chat on Facebook Live. Highlights:

Question: How will Meghan Markle change the royal family? You quote a friend of hers who says: “She is going to bring a lot of diversity and new ideas, new ways of doing things. She is not just going to blend in to the royals.” Do you agree? And how will she talk to the royal family about these issues?

Morton:She’s going to be someone who will be eloquent and articulate when it comes to arguing for diversity and someone who will challenge existing mores. She’s a team player … (but) she’s still finding her feet. She doesn’t really know her way around London, she doesn’t know the geography of the country, the culture of the country, so she’s not going to start putting her size 6s into a thousand-year-old institution. But having said all that, she is a modern woman. She had a blog, she’s into social media and the world of brand ambassadors. She’ll be seen very much as a role model for aspiring young women.

Q: Why did Queen Elizabeth II approve this match? Was it that tea she had with Meghan? Or she just wants to see her grandson happy?

Morton: As far as Meghan’s concerned, (the queen) was more focused on Prince Harry. How changed he was. He was an angry young man, a young man who fell out of bars, picking fights with paparazzi. By his own admission he was lost and alone. The presence of Meghan — the settling presence of Meghan — as someone who will bring stability into his life will obviously bring approval from his grandmother. The queen’s a shrewd judge of character. I find it very interesting that these days, she seems more relaxed, more informal than any time I’ve ever seen her. … I think she’s relaxed because she now can see that her two grandsons, William and Harry, are authentic stars who will push the monarchy forward in a good, solid way for the next 60, 70 years.

Q: What is Meghan going to have to give up to take on this royal role? She is giving up her acting career. She gave up her popular blog.

Morton: Joining the royal family is a massive transition. She’s got to learn a new culture, a new sense of humor, how to find a ripe avocado, where’s there a decent yoga studio, all these little quotidian details of life, if she wants to make a success of living in London.

Meghan Markle in spiky heels at a reception with delegates from the Commonwealth Youth Forum in central London on April 18, 2018.(Photo: Yui Mok, AFP/Getty Images)

Q:Princess Diana made tape recordings for your Diana book, which was reissued last year on the 25th anniversary. Are there secret Meghan tapes?

Morton: I wish!

Q: Were you able to talk to Meghan?

Morton: No.

Q: Meghan is estranged from her Markle half-siblings and you don't expect them at the wedding, correct?

Morton: As I speak now, no member of the Markle family has been invited to the wedding. And that also includes her father, Tom Markle Sr. It may change, I hope it does change. … I would counsel her to think again, because I think it probably would overshadow the wedding to see Doria (Ragland, her mother) walking down the aisle and not her father.

Q:Meghan is making a splash with her clothing, but are you seeing any evidence that she’s changing the way she dresses because she’s joining the royal family?

Morton: Well, the heels are still pretty high. But the dresses are a lot longer — (below) the knee, as opposed to way above the knee. So yeah, you’re seeing a rather more demure Ms. Markle.

Q: As a commentator, what’s the one thing you'll be looking for at the wedding?

Morton: At the last royal wedding (William and Kate's), everything was about Pippa Middleton’s rear and the hats worn by princesses Eugenie and Beatrice, so it’s those unexpected things that will make the headlines. For me, I’m looking to see the picture of the queen with Doria Ragland, the longest serving British monarch in history standing next to a woman who is a direct descendant of slaves. And, obviously, we’re all looking for the kiss.